From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f69.google.com (mail-wm0-f69.google.com [74.125.82.69]) by kanga.kvack.org (Postfix) with ESMTP id B44416B0279 for ; Fri, 16 Jun 2017 08:20:18 -0400 (EDT) Received: by mail-wm0-f69.google.com with SMTP id 70so3531169wme.7 for ; Fri, 16 Jun 2017 05:20:18 -0700 (PDT) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id o30si2019086wra.335.2017.06.16.05.20.07 for (version=TLS1 cipher=AES128-SHA bits=128/128); Fri, 16 Jun 2017 05:20:07 -0700 (PDT) Date: Fri, 16 Jun 2017 14:20:05 +0200 From: Michal Hocko Subject: [RFC] ubsan: signed integer overflow in mem_cgroup_event_ratelimit Message-ID: <20170616122005.GM30580@dhcp22.suse.cz> References: <20170616121026.GE20222@alitoo> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170616121026.GE20222@alitoo> Sender: owner-linux-mm@kvack.org List-ID: To: Alice Ferrazzi Cc: hannes@cmpxchg.org, vdavydov.dev@gmail.com, cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org [your email seems to be corrupted - here is a repost with reconstructed header] On Fri 16-06-17 21:10:26, Alice Ferrazzi wrote: > Hello, > > a user reported a UBSAN signed integer overflow in memcontrol.c > Shall we change something in mem_cgroup_event_ratelimit()? > > ================================================================================ > kernel: UBSAN: Undefined behaviour in mm/memcontrol.c:661:17 > kernel: signed integer overflow: > kernel: -2147483644 - 2147483525 cannot be represented in type 'long > int' > kernel: CPU: 1 PID: 11758 Comm: mybibtex2filena Tainted: P O > 4.9.25-gentoo #4 > kernel: Hardware name: XXXXXX, BIOS YYYYYY > kernel: e9a3bd64 d1f444f2 00000007 e9a3bd94 7fffff85 e9a3bd74 d1fc8ffe > e9a3bd74 > kernel: d2b4ef1c e9a3bdf8 d1fc934b d28b15c0 e9a3bd98 0000002d e9a3bdc0 > d2b4ef1c > kernel: 0000002d 00000002 3431322d 33383437 00343436 d1700ca2 00000000 > ecb4effc > kernel: Call Trace: > kernel: [] dump_stack+0x59/0x87 > kernel: [] ubsan_epilogue+0xe/0x40 > kernel: [] handle_overflow+0xbb/0xf0 > kernel: [] ? update_curr+0xe2/0x500 > kernel: [] __ubsan_handle_sub_overflow+0x12/0x20 > kernel: [] memcg_check_events.isra.36+0x223/0x360 > kernel: [] ? cpumask_any_but+0x31/0x60 > kernel: [] mem_cgroup_commit_charge+0x55/0x140 > kernel: [] ? ptep_clear_flush+0x72/0xb0 > kernel: [] wp_page_copy+0x34e/0xb80 > kernel: [] do_wp_page+0x1e6/0x1300 > kernel: [] ? check_preempt_curr+0x110/0x230 > kernel: [] ? kmap_atomic_prot+0x126/0x210 > kernel: [] handle_mm_fault+0x88b/0x1990 > kernel: [] ? _do_fork+0x155/0x5b0 > kernel: [] __do_page_fault+0x2de/0x8a0 > kernel: [] ? SyS_clone+0x27/0x30 > kernel: [] ? __do_page_fault+0x8a0/0x8a0 > kernel: [] do_page_fault+0x1a/0x20 > kernel: [] error_code+0x67/0x6c > kernel: > ================================================================================ > > Thanks, > Alice -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org